Convectively coupled Kelvin waves and the basic state

This study examines the relationship between convectively coupled Kelvin waves and the properties of their background environment. Interest in this topic stems from recent idealized modeling work, which shows that the relative importance of temperature vs. moisture in convection-wave coupling is strongly influenced by the intensity of the background convection. Meanwhile observations reveal a broad range of Kelvin wave phase speeds, with the slowest moving waves appearing generally over the convectively active tropical warm pool region. To address whether this phase-speed dependence of the waves can be attributed to variations in the strength of the background convection (as opposed to doppler shifting by the mean flow), we perform statistical composites of model reanalysis data, together with explicit simulations of convection-wave coupling.